Treatment of artificial silk



Patented on. 11, 1939 2,178,402 TREATMENT or ARTIFICIAL smx ThcodoorKoch, Oosterbeek, Netherlands, assignor to American Enka Corporation,Enka, N. 0., a

corporation of Delaware Application January 27, 1937, Serial No. 122,663

No Drawing.

4 Claims.

The present invention relates to the treatment of textile fibers andmore particularly to the lubrication and protection of yarns, threads,filaments and the like consisting wholly or par- 5 tially of natural orartificial materials.

Whereas it is intended that the treatment of natural fibers be included,the invention will be described in its specific application to fibers ofartificial origin. After cellulosic solutions such as viscose have beenextruded to form threads and the final product has been finished, it isnormally subjected to several different textile operations inorder tofabricate the thread into a merchantable article. These textileoperations, namely, knitting, weaving or braiding must be conducted bycomplicated machinery, which exposes the thread to considerable wearunless it is otherwise treated with a lubricative and protective medium.In addition to the damage to the thread occurring as a result of thewear between the thread and the mechanical parts with which it comes in,frictional contact, a certain amount of friction takes places betweenthe threads themselves during the process of fabrication. Thesedifiiculties are greatly aggravated by the use of modern high speedmachines and unless the thread is coated with a protective medium,breaking, rupturing and uneven fabrication will occur.

In order to overcome the foregoing obstacles the textile industry, andprincipally the rayon industry, has employed many different lubricatingagents. Lubricating agents alone such as mineral oils can not be used,as they impart to the thread a harsh feeling and are notselfemulsifiable with'aqueous solutions. Moreover,

. if lubricants are used without the addition of emulsifying andsoftening agents, the quantity necessary to provides smooth surfacewould 40 be so large that it would be impractical.

In providing an improved lubricating composition having certainadvantages over the art, United States Patent No. 2,025,435 of AleidusG. Bouhuys discloses and claims a composition for treating artificialthreads. Such a composition contains a lubricant, an emulsifying agentand a solvent. This solution has been found to give beneficial resultsmore specifically described in the patent.

It has now been determined that materials for protecting threads musthave additional pre requisites for effecting optimum fabricatingoperations. 'By extensive experimentation'it has been concluded thatcertain emulsifying and 55 softening compositions used in combinationwith the lubricants have impaired the wetting out properties of themixture. In other words, in an effort to promote emulsification of thelubricatlng compositions, the added substances have to a great extentpresented other serious drawbacks to the use of such a mixture. Now, inorder to reduce the friction between the threads and the mechanicalparts to a minimum, the lubricating composition must form a coherentfilm over the threads and must also have the characteristic of 10spreading perfectly over the metal parts with which the thread comes incontact. This property is known as wetting out the various surfaces.When all of the. surfaces properly wet out, considerably smallerquantities of the lubri- 15 eating mixture may be employed with improvedresults.

It is, therefore, the object of the present invention to provide amethod for treating textile fibers and more specifically threads ofcellulosic 2o origin whereby the fibers or threads will have thenecessary lubricating and emulsifying properties and will have theadditional characteristic of forming an effective film on the surface ofthe thread and all other surfaces with which the treated thread comes incontact.

Another object of the invention is the provision of a novel lubricatingcomposition which will wet out steel and porcelain surfaces as well asthe surface of the thread per se.

It is still further contemplated to treat threads of artificial originwith a lubricating composition which contains an emulsifying agent, asoftening agent and a solvent for the mixture, said solution effectingstable emulsions with water in any concentration.

An additional object of the present invention is to provide a protectivemedium for artificial silk threads which is lime-resistant, that is, itappreciably resists forming precipitates with the 40 soluble salts ofalkaline earth metals.

According to the present invention one of the most important aspects isthe proper selection of the materials to be used in combination. Thetypes of lubricating compositions which will form emulsions and alsocoherent films on cellulose and metal surfaces are rather limited and inorder to determine which ones will wet out both the cellulose surfaceand metallic surfaces, it becomes necessary to conduct certain tests.The so following test for wetting out has been successfully applied. Thcomposition is dissolved in a volatile solvent and spread over thesurface to be tested. After evaporation of the solvent, if a continuousand coherent liquid film of the com- 5r hygrosoopicity and limeresistance,

position remains on the surface, the lubricating composition has theproperty of what is termed,

lowing lubricating compositions were adjudged to wet out cellulose andsteel surfaces. Lubricants were used such as mineral oils and certainhigher fatty acid esters of monohydric alcohols and particularly thelower monohydric alcohols mixed with emulsifying agents such assulphonated olive oil and organic derivatives of amines. As softeningagents which were used in the combination and'did not retard the wettingout power of the mixture were materials such as glycerine andsulphonated alcohols.

The following table exemplifies the various groups of materials and anycompound from either one of the groups may be mixed with one or more ofthe compounds of the other group and the resulting composition willexhibit the necessary characteristics for treating threads of natural orartificial origin:

' Lubricants Emulsifying and softening Fatty acid esters agents (a)Butyl stearate Sulphonated alcohols (b) Butyl myristate (a) Gardinols(c) Ethyl palmitate Sulphonated olive oil Mineral oil 0 r g a n i cderivatives of Higher fatty acids amines (a) Oleie acid (a) Amine soapof oleic cid table, a solvent is usually desirable in order to.

provide a clear solution. For example, it would ordinarily be toadvantage to add a small quantity of oleic acid or Carbitol to obtaincomplete miscibility of the other ingredients and provide a clearemulsion with water.

The importance of the proper selection of materials to be employed mightbe shown more clearly by pointing out thatcertain emulsifying andsoftening agents formerly employed destroy the wetting power of thelubricant for one or more surfaces with which it comes in contact. Forinstance, sulphonated castor oil, Monopol oil and Prestabit oil act topromote emulsification but prevent the composition from wetting outeither the thread or the metal parts, and in addition, they leave stickyresidues which are objectionable. Compounds which have-been frequentlyused as both softening and emulsifying agents are the metallic soapssuch as alkali present composition has several advantageous propertieswhich were formerly lacking, namely,

lubrication, emulsification, softening, wetting out,

In addition to these properties, when esters are employed as thelubricant, they will readily saponify and thereby increase thesolubility of the mixture.

The emulsifying agents employed normally impart to the mixture thenecessary hygroscopicity and lime resistance, that is, the compositionwill have the tendency to absorb moisture from the air and are stabletoward calcium and magnesium, as they will not form precipitates withalkaline earth metals. Furthermore, the emulsion is resistant towardbreaking. in the dye bath in the presence of soluble inorganic sulphatesand as a result will not hinder the action of the dye if left in thethread during. the dyeing operation.

It is to be understood that the proportions of the lubricant, emulsifierand softener may be I varied in accordance with the specific applicationof the composition. Examples of compositions which have been determinedto give sat sfactory results are given below:

Example 1.-A simple lubricating composition may be formed according tothe principles of this invention by thoroughly mixing about 75 parts byweight of butyl stearate with about 25 parts by weight of sulphonatedolive oil and a sufficient quantity of oleic acid to render the mixturea clear solution. readily emulsifiable in water in any proportion andgives a very staole emulsion. It will form a coherent and an effectivefilm on the surface of the thread and on the surface of the metallic andporcelain parts with which the thread comes in contact. This effectivewetting out of all surfaces permits the application of smaller amountsthan has hitherto been possible, For example, the thread may beimpregnated with amounts ranging from 0.1% to 0.5% of the weight of thethread and friction will be reduced to a minimum.

Example 2.Another lubricating and softening composition may be preparedin accordance with the concept of this invention by employing alubricant consisting of a mixture of 40 to by weight of mineral oil and5 to 25% by weight of butyl stearate. To this lubricant per se is addedabout 5 to 15% by weight of diethyl cyclohexylamine and about 10 to 30%by weight of oleic acid. Most of the oleic acid reacts with the amine toform the oleate. A small percent of free oleic acid remains whicheffects a clear solution, This composition has such a high degree ofwetting out that small amounts ranging from 0,25 to 1.5% by weight ofthe thread may be successfully employed.

In both of the foregoing examples if additional softening of the threadis necessary, a small amount, for example, from 1 to 5% by weight of asulphonated alcohol may be substituted in the mixture in place of thecorresponding amount of emulsifying agent.

Example 3.One specific composition which is found to provide aneffective protective medium for the thread is 65% by weight of mineraloil, 10% by weight of butyl stearate, 8% by weight of diethylcyclohexylamine, 16% by weight of oleic acid and 1% by weight ofglycerine.

The lubricating compositions made by any of the preceding examples arein accordance with the principles of this invention and may be appliedto the textile material by dipping skeins in the treating emulsion or byforcing the emulsion through wound spools, cakes v.or other'packages ofthread, or by applying the lubricating mixture directly to the thread.The composition r:

The resulting composition is finely dispersed and stable that nofiltering action takes place and hence there is an even distribution ofthe composition throughout all parts 70 scope thereof. The inventionherein described is to be limited only within the scope of the appendedclaims. a

What I claim is:

1. A lubricating-composition for use in the treatment oi. yarns o!artificial origin comprising a solution formed of a mixture of mineraloil and butyl stearate, a substituted hexylamine and a solvent for themixture.

2. A lubricating composition for use in the treatment of yarns oi!artificial origin comprising 40 to 70%by weight of mineral oil, 5 to byweight of butyl'stearate. 5 to 15% by weight of diethyl cyclohexylamineand 10 to by weight of oleic acid.

3. A thread having improved characteristics and especially adaptable forweaving and knitting purposes comprising a core of cellulose origin anda film thereon formed 0! a mixture of mineral oil and butylstearate anda substituted hexylamine said mixture being dissolved in a solvent.

4. A thread having improved characteristics and especially adaptable forweaving and knitting purposes comprising a core 0! cellulosic origin anda film thereon formed of a mixture of 40 to percent by weight of mineraloil, 5 to 25 per-

